Position control device

ABSTRACT

A position control device wherein a supported track is affixed to and movable with a part of an apparatus on which the control device is used. Said movement by said track actuates switches radially disposed at a fixed position about said track by the contact of said switches by switch-actuating means adjustably disposed along said track and movable therewith.

United States Patent Cornelius E. Daly Springfield, Mass. 4,510

Jan. 2], 1970 Dec. 7, I971 Koehring Company Milwaukee, Wis.

Inventor Appl. No. Filed Patented Assignee POSITION CONTROL DEVICE 7 Claims, 2 Drawing Figs.

11.8. C1 ..200/153 LA Int. Cl H01h 3/42 Field of Search 200/153,

References Cited UNITED STATES PATENTS 8/1953 Doutt 3,192,350 6/1965 Horberg ZOO/153.12 3,159,875 12/1964 264/53 3,176,088 3/1965 ZOO/153.12 3,433,907 3/1969 ZOO/153.12 3,472,977 10/1969 200/47 Primary Examiner-Milton O. Hirshfieild Assistant Examiner-R. Skudy Attorney-Chapin, Neal and Dempsey ABSTRACT: A position control device wherein a supported track is affixed to and movable with a part of an apparatus on whichthe control device is used. Said movement by said truck actuates switches radially disposed at a fixed position about said track by the contact of said switches by switch-actuating means adjustably disposed along said track and movable therewith. I

POSITION CONTROL DEVICE BACKGROUND The present invention relates to an improved position control device which may be used on apparatus which has one part thereof moving relative to another part thereof. It is particularly suited for use on such an apparatus where a plurality of predetermined positions must be assumed during the relative movement of the parts.

A position control device is basically an electromechanical assembly capable of adjusting the mechanical position of a machine to any one of a plurality of preselected positions and/or of controlling operations of a machine at any predetermined point during its cycle.

While such devices have found use in a great many industrial applications, their value is best realized in the chemical processing industry, especially in the synthetic plastics molding field.

Even though there are a number of position control devices available, they are for the most part unsuitable for a variety of reasons, such as being too large or too delicate, some are difficult to install, some only operate with fixed preselected positions, while others have a low number, e.g., two, of preset positions, or are difficult to adjust.

Therefore, it is an object of this invention to provide a position control device having unlimited position control selection.

It is another object of the present invention to provide a position control device that is compact, yet sturdy.

It is a further object of the present invention to provide a position control device which is easily installed and easily adjusted in the field.

It is still another object of the present invention to provide a position control device which will have universal application, especially with long stroke processing equipment. I

The above and other objects and advantages of the device of the present invention will become apparent with consideration of the following disclosure in conjunction with the drawings wherein:

FIG. 1 is a front elevation view of the position control device of the present invention; and

FIG. 2 is a section view taken along the line 2-2 of FIG. I.

Referring primarily to FIG. 1, a position controller assembly is indicated by the numeral 10. As shown, the device is comprised of three basic parts, a housing or electrical enclosure 12, a track or stroke rod 14, and support and guide means for the track 14 in the form ofa guide or support bracket 16.

As shown in FIGS. 1 and 2, the housing 12 is basically a rectangular-shaped box structure which is affixed to the support structure of a machine (such as partially shown in phantom in FIG. 2) through the rear wall 18 of the enclosure 12 by bolts 20 or the like.

The front wall or face 22 of the enclosure 12 is provided with a concave portion 24. The purpose of this portion will be more fully explained below.

The enclosure is also provided with a cover member 26 removably mounted thereon by studs 28.

The guide or support bracket 16 is disposed on the forward side of the enclosure 12 by studs 30. As best seen in FIG. 2, the bracket 16 is provided with an upwardly extending flange 32 which terminates in a T-section 34. The bracket 16 is disposed so that the vertical axis of the upwardly extending flange 32 intersects the center point of the concave portion 24 of housing 12. While this dimensional characteristic is not critical, it is desirable from a manufacturing standpoint.

The stroke rod or track 14 is an elongated rod which may be in the form of a square or rectangle. While the track 14 is shown as a hollow tubular extrusion with a slot 36 in the bottom wall 38 thereof, as will become clear to those skilled in the art, it may also be a solid rod having a machined T-shaped slot in the bottom thereof.

At its forwardmost end 39, the track 14 is affixed to .the rear surface 40 of a movable part of an apparatus, such as a molding machine head platen, which is to be controlled by the position control device. This attachment is simply accomplished by the use of a stud and nut assembly 42 disposed in the end of the track M.

The track 14 is supported for rectilinear motion relative to the enclosure 12 by bracket 16 wherein the flange 32 passes through slot 36 so as to permit the T-section 34 to support the track 14 by bearing against the top wall 44 and side walls 46 thereof. In order to provide for smooth nonbinding relative movement between the track 14 and the T-section 34, the contact surfaces of the T-section may be coated with Teflon or the like.

Alternatively the T-section 34 may be a separate part which is removably mounted on the flange 32. In such a case, the separable T-section member may be formed of a molded synthetic plastic material having a low coefficient of friction, such as Delrin.

As best seen in FIG. 2, the track 14 is disposed on the bracket 16 so that its axis is perpendicular to the forward side of the enclosure 12. As further depicted, the track is positioned within the arcuate segment formed in the face of the enclosure 12 by the concave portion 24.

A plurality of electrical contact switches 48 are disposed in the wall of the concave portion 24 in radial relationship with the track 14. As best seen in FIG. I, the switches 48 are preferably disposed in the same plane and extend radially inwardly toward the track 14. The electrical connections for each of the switches 48 are located in the interior of housing 12.

A plurality of switch-activating :means are disposed on the track 14, for the sequential actuation of said switches. As shown, such means comprises a clamp member 50 with a promontory or cam surface 52 thereon. As best seen in FIG. 2, the clamp member is generally C-shaped and is held in engagement with the track by setscrew 54 or the like.

Each switch is provided with at least one actuating means and as such, the cam surface 52 on a particular clamping member 50 for a specific switch 48 is positioned so as to only contact one specific switch.

The track 14 is also provided with a graduated scale 56 disposed on the front thereof. The length of the scale corresponds in length to the distance of travel of the apparatus to which the position control device of the present invention is adapted and is used in association with a position pointer 57 which is a part of each clamping member 50.

Finally, and end cap 58 is disposed on the free end of the track 14 for safety purposes.

OPERATION The operation of the position controller of the present invention is best explained by making; reference to its use with a specific device. To this end, reference is made to US. Pat. No. 3,159,875 to Stutz .et al., entitled "Automatic Molding Press.

In molding press described in the above-noted patent, the position controller of the present invention would be affixed to the molding press support structure behind the movable head platen with the track 14 affixed to the rear of the movable head platen.

With the movable head platen of the molding apparatus in its maximum open position, clamping member 50a is positioned on the track 14 so that the cam surface 52 therein is in contact with contact switch 48a. At this juncture, clamping member 50c is positioned on the track at a point away from clamping member 50a equal to or slightly less than the total travel of the movable head platen of the molding apparatus which would bring the same into molding relationship with the stationary head platen of the molding apparatus.

Once the above has been accomplished, clamping members 50d, 50c and 50b positioned as desired along the track 14 between clamping members 50a and 50e.

With the apparatus in its open position, a simplified cycle would be as follows:

. Closing mold The cycle is started by the manual operation of a starting switch whereby the contact switches 48a, 12, c and d are deactivated and the mold-closing travel begins.

2. Stop travel When the cam surface 52 on clamping member 502 contacts switch 48c the mold-closing travel is stopped. At this point, the mold is typically fed, steamed, drained and cooled, such operation being automatically timed by the molding apparatus.

. Air ejection -Once the cooling timer is timed out, the mold starts to open. At this point, switches 48 a, b, c and d are activated. As the opening of the mold continues, cam surface 52 of clamping member 50d contacts switch 48d whereby part ejection air is turned on so as to loosen the molded products from their mold cavities.

4. Mechanical ejection With the air ejector still activated and the mold-opening travel still continuing, cam surface 52 of clamping member 500 trips switch 48c whereby mechanical part ejection means is activated so as to totally remove the mold parts from their mold cavities.

5. Air ejection ofi -With the continuing mold-opening travel, cam surface 52 of clamping member 50b contacts switch 48b whereby the part ejection air is turned off.

6. Cycle stop The mold opening travel continues until cam surface 52 of clamping member 50a trips switch 48a whereby the mold-opening travel and the cycle is terminated and a preset recycling timer is actuated in preparation for the next cycle.

The operation of the device of the present invention is obviously controlled by an electrical circuit connected into the cir' cuitry of the molding apparatus (not Shown) which does not form a part of this invention.

As should be clear to those skilled in the art, the concave portion 24 of the enclosure may be enlarged so as to accommodate more switches and additional actuating means may be provided on the track and positioned as desired.

From the above description, it should also be clear that the position controller of the present invention is easily installed and economical to manufacture. For example, most of the parts may be cast or bought as standard items which require a minimum of machining.

What is claimed is:

l. A position control device which comprises an elongated track, means for supporting said track for rectilinear movement, a plurality of contact switches disposed radially about said track in plane perpendicular to the axis thereof and switch-actuating means for each of said switches, said switchactuating means being adjustably mounted on said track and movable therewith whereby rectilinear movement of said track actuates said switches.

2. The position control device of claim 1 wherein said switch actuating means comprises a clamping member having a cam surface thereon for actuating said switches.

3. The position control device of claim 1 wherein said means for supporting said track comprises a support bracket having an upwardly extending flange terminating in a T- shaped section, said track being slidably engageable with said T-shaped section.

4. The position control device of claim 3 wherein said T- shaped section is removably disposed on said upwardly extending flange of said support bracket.

5. The position control device of claim 4 wherein said T- shaped section is formed from a moldable synthetic plastic.

6. A position control device which comprises a. a housing having a concave portion in the face thereof,

b. an elongated track disposed for rectilinear movement relative to said housing,

c. a support bracket slidably engageable with said track for supporting same during said rectilinear movement,

d. a plurality of contact switches mounted on said housing and extending into said concave portion radially and inwardly towards said track, said switches being disposed in a plane perpendicular to the rectilinear movement of said track and e. switch-actuating means for each of said contact switches adjustably disposed on said track and movable therewith whereby rectilinear movement of said track actuates said switches.

7. The position control device of claim 6 wherein said switch-actuating means comprises a clamping member having a cam surface thereon for actuating said switches. 

1. A position control device which comprises an elongated track, means for supporting said track for rectilinear movement, a plurality of contact switches disposed radially about said track in plane perpendicular to the axis thereof and switch-actuating means for each of said switches, said switch-actuating means being adjustably mounted on said track and movable therewith whereby rectilinear movement of said track actuates said switches.
 2. The position control device of claim 1 wherein said switch actuating means comprises a clamping member having a cam surface thereon for actuating said switches.
 3. The position control device of claim 1 wherein said means for supporting said track comprises a support bracket having an upwardly extending flange terminating in a T-shaped section, said track being slidablY engageable with said T-shaped section.
 4. The position control device of claim 3 wherein said T-shaped section is removably disposed on said upwardly extending flange of said support bracket.
 5. The position control device of claim 4 wherein said T-shaped section is formed from a moldable synthetic plastic.
 6. A position control device which comprises a. a housing having a concave portion in the face thereof, b. an elongated track disposed for rectilinear movement relative to said housing, c. a support bracket slidably engageable with said track for supporting same during said rectilinear movement, d. a plurality of contact switches mounted on said housing and extending into said concave portion radially and inwardly towards said track, said switches being disposed in a plane perpendicular to the rectilinear movement of said track, and e. switch-actuating means for each of said contact switches adjustably disposed on said track and movable therewith whereby rectilinear movement of said track actuates said switches.
 7. The position control device of claim 6 wherein said switch-actuating means comprises a clamping member having a cam surface thereon for actuating said switches. 